On Mon, 29 Dec 2003 15:46:37 -0500, Bill Flanigan <[email protected]> wrote: >How to specify a diode bridge to ensure its success during IEC 61000-4-5 >Surge testing (mains) to Class 3 (1kV L-L, 2kV L-G)? If the diode spec >declares a maximum peak forward surge current, how do I calculate the >current this immunity test is likely to provide? Any advice on surviving >this test?
Hi Bill: >... how do I calculate the current this immunity test is likely to provide? For L-L testing, IEC61000-4-5 specifies an effective source impedance of 2 ohms (clause 6.1). Therefore, the maximum current the generator can provide during your L-L test is 1kV / 2 ohms = 500A. For your L-G testing, the effective source impedance is 12 ohms (clause 7 and Annex B.1). This results in a maximum available peak current of 2kV / 12 ohms = 167A. Are you having diode failures, or are you just looking for guidelines? If you're having failures, are due to current stress, or are they related to voltage stress? I've tested power supplies (10-500W, open frame & PWB) for several years, and never had diode bridge failures. -- Pat Lawler [email protected] This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ieee-pses.org/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
